RMHI编码基础

r studio的总结和基础信息和做图，主要涵盖了编程和数据处理的基础知识，特别强调了R语言（一种统计程序设计语言）在数据处理和分析中的应用。图片以数据结构图的形式，系统地展示了从简单的数学计算、基本编程命令，到复杂的逻辑判断和数据处理的全过程。为初学者提供了一个全面的编程和数据处理的入门指南，特别是对于希望使用R语言进行数据分析的学者来说，具有很高的参考价值。

RMHI Coding Basis

• Basic commands
  • simple calculations: +, -,*, /,^
  • Logical statement: == equality,!=inequality, >,>=,<,<=
• Using Functions
  • sqrt(). the sqrt is function and the thing in () is arguments.
    • a lot of arguments has defalut value, and have the "name"
    • sqrt() squareroot, round(), roumnd a number log(), exp(), abs()...
  • Variable
    • ceating variables
      • age<-....
  • Vectors
    • Vectors are variables that storee multiple pieces of information
    • creating vectors: abs<-c(........)
    • Selecting vectors: abc[........], |,&,!
• Data and Package
  • First library Here function abcd<-here("abc.csv") data<-read.csv(file=abcd)) write(data,"abcd")
  • Viewing data
    • data$.vatiable data$newname<-data$variable/NULL=消失
  • Selecting from tibble
    • data$variable[1,1] whole row: [1,] whole column: [1]
  • Measurement
    • relates mesure to observation
    • operationalization
      • relates constructs to measure
      • E.g., intelligence, WAIS, IQ score are constructs, measurements, and observation.
    • Scles
      • Norminal
      • Categorical
      • Ordinal: have ordering but has no meaningful difference
      • interval: numbers are natural ordering, no ratios
      • ratio: numbers are ordering and ratios between them are meaningful
      • Discrete
      • Continuous
    • Reliability
      • test-retest: 不同时间相同测试
      • inter-rater：不同people同样measurement
      • internal consistency：theoratically equivalent versions of the measurement
  • Descpriptive of Data
    • Historgram graph show the count of the number of the observation called frequency
    • mean(data$variables, na.rm=TRUE) median quantile(data$variable,0.5) modef()/maxFreq() min() max() interquatile--quantile(data$variable, c(0.25, 0.75)/IQR() sd() range()==max()-min()
      • Summary() function can have all of the main results for the data
  • Data manipulation
    • Pipes, Tables,Grouping==%>%, table(), group_by&summarise()
    • arrange,filter,select,mutate--顺序，小孩选不要的，选出想要的，计算新的
    • pivot_wider(names_from="key",values_from="val") pivot_longer(cols那些需要组合的columns, names_to="key", values_to="val")
  • ggplot
• floor() round down, round() is 四舍五入
• R is statistical programming language